<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .header {
            height: 200px;
            width: 1100px;
            background-color: pink;
        }
        
        .banner {
            margin-top: 10px;
            height: 350px;
            width: 1100px;
            background-color: red;
        }
        
        .main {
            margin-top: 10px;
            height: 500px;
            width: 1100px;
            background-color: yellow;
        }
    </style>
</head>

<body>
    <div class="header">头部</div>
    <div class="banner">banner部分</div>
    <div class="main">主体部分</div>
</body>

</html>